The invention relates to a method for positioning a mobile unit driven by an external force in a motor vehicle as well as an apparatus for implementing the method.
When opening and closing a mobile unit driven by an external force, in particular a windowpane of a motor vehicle by means of a mobile unit driven by an external force, in particular by means of a motor vehicle window lift, it is of special importance to always know the current position of the mobile unit driven by an external force and to monitor the latter in its movement as position-exactly as possible, in order to ensure a secure base for the functionality of a jamming protection device. For this purpose mostly the position of the mobile unit driven by an external force is standardized. In case of such mobile units driven by an external force the drive is automatically switched off and if applicable is reversed, if the mobile unit driven by an external force meets in its movement an obstacle, which is located between the mobile unit driven by an external force and in particular the framework, in which the mobile unit driven by an external force moves. Here, however, there is the problem that when approaching the mobile unit driven by an external force into the closing region of the mobile unit driven by an external force due to the resistance exerted by the sealing, which is arranged at the framework, against the adjustment movement of the mobile unit driven by an external force, said resistance can be interpreted as a jamming protection situation. Furthermore, it is difficult to approach a predefined position of the mobile unit driven by an external force and to store this position and at the same time to offer the possibility to approach this position repeatedly.
From DE 100 28 038 A1 a method is known to determine the position of an element driven by the drive shaft of a direct current motor within a pre-determined motion distance between two block positions. The position is determined by evaluating the current ripples contained in the armature current signal.
In this context, when moving the driven element into a defined block position a standardization by the system is effected. When approaching the driven element into a block position the direct current motor is disconnected from the mains before reaching the block position defined by the system and is again actuated after a pre-determined period of time for ultimately approaching the driven element into the block position. After the driven element was brought into its mechanically defined block position, this block position is standardized by the system. This standardization at the upper mechanical stop of the driven element is supposed to counteract against the possibility, which exists, if a closing system with different kinetic energy, i.e. with different speed, drives against a mechanical stop. By this different kinetic energy the point of reference can shift, in particular in case of a soft, slightly resilient mechanical stop. This results in inaccuracies of the reference position. Thus, substantial difficulties arise to approach a position of free choice between the two final positions or block positions.
From DE 102 58 476 A1 a method is known for the position-dependent control of an adjusting element movable by means of an electrically driven adjusting device for the motor vehicle. Here, the adjusting device evaluates a majority of different operating modes and characteristics of a drive signal to the adjusting device, in particular by the ripples of the drive current, for identifying the position of the element. It is provided that a parameter affecting the drive movement of the adjusting device and/or a characteristic value characterizing the adjusting device is evaluated to determine an error value of the determined position of the adjusting element and that the operating modes of the adjusting device are controlled depending on the determined error value. The position is determined by means of a counting of the current ripples. This type position determination is very sensitive in case of certain conditions, for instance motor starts, high loads, fluctuations of the vehicle electrical system, variations in temperature, aging etc. amount to inaccuracies.
From DE 102 36 650 A1 an operating device for a window lift is disclosed. The operating device has an operating means to open and close a windowpane, which comprises three discrete operating zones.
In the automatic mode, if the windowpane has been completely opened or closed, when contacting a given operating zone the windowpane is moved in advantageous manner into the position it was before it has been completely opened or closed. In this context it is disadvantageous that only the last position of the windowpane can be re-approached. No preferred position, which eventually was recorded as defined, can be re-approached.
Furthermore, with known adjusting drives it is to be differentiated between a manual run and an automatic run. A manual run means insofar that the adjusting drive is only activated as long as the user actuates the switch. The automatic run means that the adjustment process is started by actuating a switch and is continued after releasing the switch, unless the adjustment process is stopped by a further switch actuation or by triggered protective functions.
It is disadvantageous with this mentioned state of the art that positioning of the mobile unit driven by an external force to an exact desired gap opening can be adjusted only with difficulties, as mostly the mobile unit driven by an external force moves very quickly. This makes several attempts necessary with each positioning of the desired gap opening, until this desired position is reached. For storing a gap opening then adjusted in this way and for positioning on a stored gap opening additional operating elements are required.
It is the object of the invention to indicate an economical and comfortable operation both for positioning a mobile part driven by an external force of a motor vehicle on a gap opening and a method for positioning a mobile unit in a motor vehicle, as well as a corresponding apparatus for implementing the method.